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<div class="titlepage"><div><div><h5 class="title">
<a name="beast.ref.boost__beast__http__read.overload2"></a><a class="link" href="overload2.html" title="http::read (2 of 4 overloads)">http::read
        (2 of 4 overloads)</a>
</h5></div></div></div>
<p>
          Read a complete message from a stream using a parser.
        </p>
<h6>
<a name="beast.ref.boost__beast__http__read.overload2.h0"></a>
          <span class="phrase"><a name="beast.ref.boost__beast__http__read.overload2.synopsis"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__http__read.overload2.synopsis">Synopsis</a>
        </h6>
<p>
          Defined in header <code class="literal">&lt;<a href="../../../../../../../boost/beast/http/read.hpp" target="_top">boost/beast/http/read.hpp</a>&gt;</code>
        </p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">class</span> <a href="../../../../../../../doc/html/boost_asio/reference/SyncReadStream.html" target="_top"><span class="emphasis"><em>SyncReadStream</em></span></a><span class="special">,</span>
    <span class="keyword">class</span> <a class="link" href="../../concepts/DynamicBuffer.html" title="DynamicBuffer"><span class="emphasis"><em>DynamicBuffer</em></span></a><span class="special">,</span>
    <span class="keyword">bool</span> <span class="identifier">isRequest</span><span class="special">&gt;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span>
<span class="identifier">read</span><span class="special">(</span>
    <span class="identifier">SyncReadStream</span><span class="special">&amp;</span> <span class="identifier">stream</span><span class="special">,</span>
    <span class="identifier">DynamicBuffer</span><span class="special">&amp;</span> <span class="identifier">buffer</span><span class="special">,</span>
    <span class="identifier">basic_parser</span><span class="special">&lt;</span> <span class="identifier">isRequest</span> <span class="special">&gt;&amp;</span> <span class="identifier">parser</span><span class="special">,</span>
    <span class="identifier">error_code</span><span class="special">&amp;</span> <span class="identifier">ec</span><span class="special">);</span>
</pre>
<h6>
<a name="beast.ref.boost__beast__http__read.overload2.h1"></a>
          <span class="phrase"><a name="beast.ref.boost__beast__http__read.overload2.description"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__http__read.overload2.description">Description</a>
        </h6>
<p>
          This function is used to read a complete message from a stream into an
          instance of <a class="link" href="../boost__beast__http__basic_parser.html" title="http::basic_parser"><code class="computeroutput"><span class="identifier">basic_parser</span></code></a>. The call will block
          until one of the following conditions is true:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
              <a class="link" href="../boost__beast__http__basic_parser/is_done.html" title="http::basic_parser::is_done"><code class="computeroutput"><span class="identifier">basic_parser</span><span class="special">::</span><span class="identifier">is_done</span></code></a> returns <code class="computeroutput"><span class="keyword">true</span></code>
            </li>
<li class="listitem">
              An error occurs.
            </li>
</ul></div>
<p>
          This operation is implemented in terms of one or more calls to the stream's
          <code class="computeroutput"><span class="identifier">read_some</span></code> function. The
          implementation may read additional bytes from the stream that lie past
          the end of the message being read. These additional bytes are stored in
          the dynamic buffer, which must be preserved for subsequent reads. If the
          end of file error is received while reading from the stream, then the error
          returned from this function will be:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
              <a class="link" href="../boost__beast__http__error.html" title="http::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">end_of_stream</span></code></a>
              if no bytes were parsed, or
            </li>
<li class="listitem">
              <a class="link" href="../boost__beast__http__error.html" title="http::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">partial_message</span></code></a>
              if any bytes were parsed but the message was incomplete, otherwise:
            </li>
<li class="listitem">
              A successful result. The next attempt to read will return <a class="link" href="../boost__beast__http__error.html" title="http::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">end_of_stream</span></code></a>
            </li>
</ul></div>
<h6>
<a name="beast.ref.boost__beast__http__read.overload2.h2"></a>
          <span class="phrase"><a name="beast.ref.boost__beast__http__read.overload2.parameters"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__http__read.overload2.parameters">Parameters</a>
        </h6>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Name
                  </p>
                </th>
<th>
                  <p>
                    Description
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">stream</span></code>
                  </p>
                </td>
<td>
                  <p>
                    The stream from which the data is to be read. The type must meet
                    the <span class="emphasis"><em>SyncReadStream</em></span> requirements.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">buffer</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Storage for additional bytes read by the implementation from
                    the stream. This is both an input and an output parameter; on
                    entry, the parser will be presented with any remaining data in
                    the dynamic buffer's readable bytes sequence first. The type
                    must meet the <span class="emphasis"><em>DynamicBuffer</em></span> requirements.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">parser</span></code>
                  </p>
                </td>
<td>
                  <p>
                    The parser to use.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">ec</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Set to the error, if any occurred.
                  </p>
                </td>
</tr>
</tbody>
</table></div>
<h6>
<a name="beast.ref.boost__beast__http__read.overload2.h3"></a>
          <span class="phrase"><a name="beast.ref.boost__beast__http__read.overload2.return_value"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__http__read.overload2.return_value">Return
          Value</a>
        </h6>
<p>
          The number of bytes transferred from the stream.
        </p>
<h6>
<a name="beast.ref.boost__beast__http__read.overload2.h4"></a>
          <span class="phrase"><a name="beast.ref.boost__beast__http__read.overload2.remarks"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__http__read.overload2.remarks">Remarks</a>
        </h6>
<p>
          The function returns the total number of bytes transferred from the stream.
          This may be zero for the case where there is sufficient pre-existing message
          data in the dynamic buffer. The implementation will call <a class="link" href="../boost__beast__http__basic_parser/eager.html" title="http::basic_parser::eager"><code class="computeroutput"><span class="identifier">basic_parser</span><span class="special">::</span><span class="identifier">eager</span></code></a> with the value <code class="computeroutput"><span class="keyword">true</span></code> on the parser passed in.
        </p>
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        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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